The present invention relates to the sweetener known as aspartame and, more particularly, to a gelatin dessert sweetened with aspartame. In addition, the invention relates to a composition for sweetening edible products and to a method for sweetening edible products.
The sweetener aspartame is a dipeptide compound which is described, in terms of most accurate chemical nomenclature, as 1-methyl-N-1-alpha-aspartyl-1-phenylalanine. In patents and literature, the dipeptide also has been referred to as aspartyl phenylalanine methyl ester and .alpha.-L-aspartyl-L-phenylalanine methyl ester. The chemical formula, preparation and use of aspartame and other dipeptide sweeteners are described, for example, in U.S. Pat. Nos. 3,492,131 and 3,642,491 to James M. Schlatter.
Since the time of aspartame's appearance as a sweetener, many workers in the field of edible food and drug products (including normally non-ingestible products such as chewing gums and chewable medicaments) have proposed the use of aspartame as a partial or total replacement for sucrose (or for other sweet mono-, di- and poly-saccharides used in place of or in addition to sucrose) in products normally sweetened therewith.
Certain of the physical-chemical characteristics of aspartame have necessitated modification of the formulation of some sucrose-sweetened products when the sucrose is replaced in whole or in part with aspartame. For example, because aspartame is about 150 times as sweet as sucrose, use of aspartame to provide the sweetening equivalent of the sucrose it replaces results in a substantial decrease in the bulk density of the product. Accordingly, if it is desired to market an aspartame-sweetened product in package and/or serving sizes equivalent to those of the sucrose-sweetened counterpart, the use of a suitable bulking agent is required. Another example relates to the poor dispersibility/solubility of aspartame, relative for example to sucrose, in certain aqueous food systems, which has led art workers to propose numerous methods and materials for making aspartame more sucrose-like in its solubility and dispersion characteristics.
With respect to organoleptic properties, and particularly sweetness perception and taste, the art generally has considered aspartame to be superior to the prior sucrose substitute of choice, saccharin, which possesses what is commonly characterized as a bitter, metallic aftertaste. However, it has been recognized that the sweetening effects of aspartame nevertheless are not truly "sucrose-like" and that simple substitution of aspartame for sucrose in sweetened products does not necessarily lead to a product similar to--or as desirable as--the sucrose-sweetened product.
Some efforts have been made to alter the sweetness perception and taste of aspartame. In U.S. Pat. No. 3,875,311 to Eisenstadt, dipeptide sweeteners, including aspartame, are characterized by the inventor as exhibiting a flat sweetness along with a slightly bitter aftertaste, and in beverages, a slightly delayed sweetness. These undesired taste effects are said to be avoided by a composition containing the dipeptide sweetener, postassium bitartrate (and/or sodium bicarbonate and/or potassium bicarbonate), and glucono delta lactone (and/or sodium or potassium gluconate) in specified ratios.
U.S. Pat. No. 3,875,312, also to Eisenstadt, similarly characterizes the taste of aspartame and other dipeptide sweeteners and proposes a composition containing dipeptide sweetener, potassium bitartrate (and/or sodium bicarbonate and/or potassium bicarbonate), and lactose and/or dextrose, in specified ratios.
U.S. Pat. No. 4,254,154, also to Eisenstadt, describes a composition said to have a sweetness close to that of natural sugar using only a small amount of dipeptide sweetener (e.g. aspartame). The composition consists of aspartame, glycyrrhizin, potassium bitartrate and a sugar (e.g, sucrose, dextrose, fructose, lactose) or a sugar alcohol (e.g., xylitol, mannitol, sorbitol).
In U.S. Pat. No. 3,934,047 to Schade, dipeptide sweeteners such as aspartame are described as having a lingering sweet aftertaste. This aftertaste is said to be eliminated by mixing with the dipeptide sweetener a small amount of either aluminum potassium sulfate and/or Naringin (4',5,7-trihydroxyflavanone-7-rhammoglucoside).
In Canadian Pat. No. 1,021,988 to Kaplow, et al., the use of depeptide sweeteners such as aspartame in beverages is said to produce a distinct oral coating or clawing sensation when the consumer drinks a significant quantity of the beverage. This effect is said to be ameliorated by including an acid-soluble whey protein in the dipeptide sweetened beverage.
In U.S. Pat. No. 4,399,162 to Okada, dipeptide sweeteners such as aspartame are said to possess a clear initial sweet taste without leaving an unpleasant bitter taste; however, it is further stated that the sweetness of the dipeptide sweeteners does not last as long as that of sucrose and that the dipeptide sweeteners "have a monotonous quality without thickness, and tend to lack roundness in their taste quality." To make the sweetening qualities of dipeptide sweeteners more like those of sucrose, the inventor proposes that the dipeptide sweetener be combined with a flavoring agent selected from sodium glutamate, sodium inosine-5'-phosphate, sodium guanosine-5'-phosphate and sodium aspartate.
Our primary objective relating to the present invention was the development of a mix which can be hydrated to provide a gelatin dessert, in which the sweetness is provided to the gelled dessert by aspartame rather than sucrose. Sucrose-containing gelatin dessert mixes per se are, of course, quite well known and generally are provided in a variety of fruit flavors, for example, lime, cherry, strawberry and orange. Sucrose-free gelatin dessert mixes sweetened with saccharin (or, in earlier times, with cyclamate or a saccharin/cyclamate combination) also are known.
Our initial findings with respect to replacement of the sucrose in a conventional fruit-flavored gelatin mix with aspartame was that the sweetness and taste of the resultant gelatin dessert was decidedly unlike that of the conventional sucrose-sweetened dessert, to a degree believed even greater than that experienced in other food systems where sucrose is replaced with aspartame. Accurate expression of the differences between the sweetness and taste of the aspartame-sweetened and sucrose-sweetened products is somewhat hampered by the inherent subjectivity of perceptions of sweetness and taste characteristics. In general, however, the aspartame-sweetened product exhibited an essentially flat sweetness profile characterized by an immediate perception of sweetness of a particular intensity and continuance of such sweetness, at essentially the same intensity, for long periods of time. This is unlike the profile for the sucrose-sweetened product wherein there is a more gradual build-up of sweetness to a peak intensity level, followed by a drop in intensity to near zero, all within a relatively brief period. In addition, the overall organoleptic response to the fruit flavors was found to differ, in an undesirable manner, in the aspartame-sweetened gelatin as compared to the action of these flavors in the sucrose-flavored product.
Resort to prior art methods for modifying sweetness and taste characteristics of dipeptide sweeteners such as aspartame was substantially unattractive and ineffective since the modifying agents employed in such methods are not particularly compatible with fruit-flavored gelatin desserts (from both an organoleptic and a functional point of view) and since such methods appear to be curing problems associated with the sweetness characteristics of dipeptides which were not present, or indeed were the antithesis of, the problems found in the fruit-flavored gelatin system.